1. Field of the Invention
The present invention relates to a technology of an engine (internal combustion engine) including a crankshaft in a substantially horizontal direction, more particularly to a technology to transmit a power of the crankshaft to a shaft which is provided in a direction perpendicular to the crankshaft.
2. Related Art
Conventionally, for example, Japanese Utility Model Publication Laid-Open No. 60-10427 discloses a technology of the engine which transmits the power of the crankshaft to the shaft provided in the direction perpendicular to the crankshaft.
A vehicle provided with the conventional engine will be described with reference to FIG. 48. Referring to FIG. 48, a work vehicle 901 is an Ackerman steering lawnmower, and the work vehicle 901 includes an engine 905 and a mower 907. The engine 905 includes a crankshaft 924 in a lengthwise horizontal direction, and the mower 907 includes an input shaft 906 which is disposed in a direction perpendicular to the crankshaft 924. A crank pulley 924a is fixed to the crankshaft 924 of the engine 905, and an input pulley 906a is fixed to the input shaft 906 of the mower 907. A counter shaft 980 is disposed in the crosswise horizontal direction below the engine 905, and a pair of right and left counter pulleys 980a is fixed to the counter shaft 980. A belt 981 is entrained about the crank pulley 924a, the pair of right and left counter pulleys 980a, and the input pulley 906a, and the power of the crankshaft 924 of the engine 905 is transmitted to the crank pulley 924a, the belt 981, the counter pulley 980a, the belt 981, the input pulley 906a, and the input shaft 906 to drive a rotary blade 907a of the mower 907.
However, in the conventional engine 905, it is necessary to ensure a space where the counter shaft 980 and the pair of right and left counter pulleys 980a are provided and a space where the belt 981 is entrained about the crank pulley 924a and the input pulley 906a with the counter pulleys 980a interposed between the crank pulley 924a and the input pulley 906a, which results in a problem in that the space limitations obstruct miniaturization of the vehicle. Additionally, there arises a problem of deteriorated working efficiency because of the need to entrain the belt 981 about the pulleys 924a, 980a, and 906a after the engine 905 is attached to the vehicle.